The following crustaceans have been collected at the island: 



Table 5. Arthropods at Rincon Island 



Common Name 



Scientific Name 



Acorn barnacle 



Balanus cariosus [Pallas) 



Acorn barnacle 



Balanus ovenatus Bruguifere 



Acorn barnacle 



Balanus glandula Darwin 



Acorn barnacle 



Balanus tintinnabulum [Linnaeus) 



Rock crab 



Cancer antennarius Stimpson 



Yellow crab 



Cancer anthonyi Rathbun 



Red crab 



Cancer productus Randall 



Pistol shrimp 



Crangon dentipes [Guferin) 



Red rock shrimp 



Rippolysmata califomioa Stimpson 



Moss -covered crab 



Loxorhynohus orispatus Stimpson 



Sheep crab 



Loxorhynchus grandis Stimpson 



Spider crab 



Loxorhynghus sp. 



Goose barnacle 



Mitella polymerus [Sowerby) 



Striped shore crab 



Pachygrapsus cvassipes Randall 



Hermit crab 



Paguristes turgidus [Stimpson) 



Shrimp 



Pandalus gumeyi Stimpson 



Spiny lobster 



Panulirus interruptus [Randall) 



Porcelain crab 



Petrolisth.es oinotipes Randall 



Kelp crab 



Pugettia producta [Randall) 



Masking crab 



Sayra acutifrons Dana 



Bent-back shrimp 



Spirontoaaris hrevirostris [Dana) 



Mollusca : Possibly the greatest increase of numbers in any one phyliom 

 since the construction of the island is in the mollusks. The greatest 

 biomass consists of the mussel beds in the upper littoral zone. Studies 

 of samples taken from this area indicate that a cluster 10 inches in dia- 

 meter contains an average of 2,600 individuals with 11 phyla represented. 

 This indicates the fundamental part the mollusks play in the establishment 

 of a mature, well-balanced reef community. 



The 61 species present represent four classes of mollusks with the 

 gastropods and bivalves being the most numerous forms. Many of these 

 animals are sought by divers. The California Department of Fish and Game 

 planted some of the more sought-after species of abalone, but within a 

 year most of these had been collected by sport divers. This is the only 

 group of animals to be artificially introduced to the island; all others 

 have been introduced through larval forms being brought in by the normal 

 ocean currents. 



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